cal = CALendar calendar日历, 历法
cat = CATenate 连接, 使连续
cd = Change Directory
chgrp = CHange GRouP
chmod = CHange MODe
chown = CHange OWNer
chsh = CHange SHell
cmp = compare
cobra = Common Object Request Broker Architecture
comm = common
cp = CoPy
cpio = CoPy In and Out
cpp = C Pre Processor
cron = Chronos 希腊文时间
cups = Common Unix Printing System
cvs = Current Version System
daemon = Disk And Execution MONitor 这个词应该出现在计算机之前吧，挺有人缘的
dc = Desk Calculator
dd = Disk Dump
df = Disk Free
diff = DIFFerence
dmesg = diagnostic message
du = Disk Usage
ed = editor
egrep = Extended GREP
elf = Extensible Linking Format
elm = ELectronic Mail
emacs = Editor MACroS
eval = EVALuate
ex = EXtended
exec = EXECute
fd = file descriptors
fg = ForeGround
fgrep = Fixed GREP
Fish = the Friendly Interactive SHell
file = file 查看文件类型，是否是二进制等
fmt = format
fsck = File System ChecK
fstab = FileSystem TABle
fvwm = F*** Virtual Window Manager
gawk = GNU AWK
gcc = general public licence (GNU) compiler collection 编译程序会产生二进制a.out文件
gpg = GNU Privacy Guard
grep = Global search regular expression and print out line
groff = GNU troff
hal = Hardware Abstraction Layer
joe = Joe's Own Editor
ksh = Korn SHell
lame = Lame Ain't an MP3 Encoder
lex = LEXical analyser
lisp = LISt Processing = Lots of Irritating Superfluous Parentheses
ln = LiNk
lpr = Line PRint
ls = list
lsof = LiSt Open Files
m4 = Macro processor Version 4
make = make
man = MANual pages 之前曾困惑过一段时间，被人笑话：多看man，少看woman
mawk = Mike Brennan's AWK
mc = Midnight Commander
MIME = Multipurpose Internet Mail Extensions
mkfs = MaKe FileSystem
mknod = MaKe NODe
motd = Message of The Day
mozilla = MOsaic GodZILLa
mtab = Mount TABle
mv = MoVe
nano = Nano's ANOther editor
nawk = New AWK
nl = Number of Lines
nm = names
nohup = No HangUP
nroff = New ROFF
od = Octal Dump
passwd = PASSWorD
pg = pager
pico = PIne's message COmposition editor
pine = "Program for Internet News & Email" = "Pine is not Elm"
ping = Packet InterNet Groper
pirntcap = PRINTer CAPability
popd = POP Directory
pr = pre
printf = PRINT Formatted
ps = Processes Status
pty = pseudo tty
pushd = PUSH Directory
pwd = Print Working Directory
rc = runcom = run command, rc还是plan9的shell
rev = REVerse
rm = ReMove
rn = Read News
roff = RunOFF
rpm = RPM Package Manager = RedHat Package Manager
rsh, rlogin, rvim中的r = Remote
rxvt = ouR XVT
seamoneky = 我
sed = Stream EDitor
seq = SEQuence
shar = SHell ARchive
slrn = S-Lang rn
ssh = Secure SHell
ssl = Secure Sockets Layer
stty = Set TTY
su = Substitute User 或 Switch User（前者较常见）
sudo = superuser / substitue user do 在ubuntu下更倾向于superuser，因为它代表了root权限
svn = SubVersioN
tar = Tape ARchive
tcsh = TENEX C shell
tee = T (T形水管接口)
telnet = TEminaL over Network
termcap = terminal capability
terminfo = terminal information
tex = τέχνη的缩写，希腊文art
tr = traslate
troff = Typesetter new ROFF
tsort = Topological SORT
tty = TeleTypewriter 电传打字机？没用过。不知道与ubuntu的text界面是怎么联系起来的。
twm = Tom's Window Manager
tz = TimeZone
udev = Userspace DEV
ulimit = User's LIMIT
umask = User's MASK
uniq = UNIQue
vi = VIsual = Very Inconvenient 后面的那个是别人附会的吧，不方便为什么会有那么多人用。不过像我等初学者确实用不惯，vim 稍微好一点。
vim = Vi IMproved
wall = write all
wc = Word Count
wine = WINE Is Not an Emulator 太搞了，和GNU's Not Unix有得一拼
xargs = eXtended ARGuments
xdm = X Display Manager
xlfd = X Logical Font Description
xmms = X Multimedia System
xrdb = X Resources DataBase
xwd = X Window Dump
yacc = yet another compiler compiler
pwd = Print work diretory